Quote Originally Posted by islaydarkblue View Post
This is a subject that I know a bit about because from 2004 until 30th November 2006 I was a member of the Islay Energy Trust steering group. On 1st December 2006 Islay Energy Trust came into being with the steering group being disbanded the night before.
Ideally solar panels should be installed on an area of roof that is south west facing and there has to be enough space for a minimum of 2.8KW of solar panels. However there is a house in the former Elgin Terrace area of Dundee which has solar panels on the roof which are facing East. Goodness knows which firm installed these solar panels but they must have been desperate for a sale.
A ground source heat pump is very expensive to install and you need a large garden to do so. Ideally ground source heat pumps should be installed when a new housing development is being built.
About 15 years ago a housing association built a small housing development in Bowmore, Isle of Islay and ground source heat pumps were installed when the houses were being constructed with taxpayers money paying for the cost of the development.
However there was one small problem. The contractors installing the ground source heat pumps made a mistake which resulted in the houses being freezing cold in the winter months and boiling hot during the summer months.
The contractors had installed the ground source heat pumps the wrong way round.
I only found out about this mistake as I knew the local electrician on Islay who was awarded the contract to fix the ground source heat pumps to ensure that they worked at the correct time. The housing association attempted to cover up this fiasco as one of the Argyll and Bute Councillors on the board of this housing association lives on Islay and represented the Kintyre and the Islands constituency.
Air source heat pumps. Several weeks ago I read an article in the Sunday Times newspaper about how long the savings from installing ‘green’ equipment to help save the planet such as solar panels, insulating your attic and hot water tank would take to recoup the cost of your outlay.
According to the article an air source heat pump is £68 per year more expensive to run than a gas boiler.
I know several people on Islay who about ten years ago installed an air source heat pump. I do not know how successful they have been but the fact that I have not heard anyone boasting that they have saved a fortune using it compared to an oil fired boiler (there is no mains gas on the island) makes me think that air source pumps are not all they are cracked up to be.
It had an interesting time as a member of the Islay Energy Trust steering group seeing how much money was squandered on ‘green’ initiatives which never happened.
Islay ,the timescales you are referring to are probably correct however they really only need UV to operate nowadays so which elevation they are mounted isn’t such a big issue ,new build now have 30% renewables which is usually solar and I have seen them on NE facing roofs.

On one of our large sites the savings from GSHP were genuinely unbelievable compared to what we had ,payback was estimated at 11 years and it broke even within 4 but that is a huge site not domestic ,air source in theory is great basically reverse refrigeration but as I said the installation was horrendous maybe better now…..